Uta and Chris Frith at their home in northwest London. Photograph: Mo Costandi

Chris Frith sits at the kitchen table in his northwest London home, cutting slices of smoked salmon into irregularly-shaped pieces and then placing them in a meticulous tiling pattern onto pieces of buttered brown bread. It is, according to his wife Uta, the kind of obsessive, repetitive behaviour that is characteristic of children with autism.

“There are people with perfectly normal personality variants who behave in an autistic-like way,” says Uta, hovering behind him as she prepares a pot of tea. “There was a time when autism was under-diagnosed and we wanted to raise awareness of it. Now, it has gone the other way – these people are diagnosing themselves, and I’m worried about over-extension of the diagnosis.”

Few can speak about the condition more authoritatively. In her 40-year career, Uta has revolutionised the study of autism, shaping the field for a whole generation of researchers. Chris, too, has been hugely influential. As an early adopter of brain imaging technologies, he studied the biological basis of thought processes, and made major contributions to our understanding of schizophrenia.

I had the pleasure of visiting “the mother and father of cognitive neuroscience” for afternoon tea at their home in northwest London earlier this year. My profile of them is now online at the SFARI website.